Lab Report: New Radar Expands View of Space Weather

Predicting the weather isn’t easy, but it’s a relative snap compared to predicting space weather. But measuring geomagnetic storms and other phenomena involving plasma in the near-Earth environment got a boost from a new pair of radars that a team led by Thayer associate professor Simon Shepherd Adv’98 built last summer on 25 acres near Christmas Valley, Ore.

TRACKING SPACE WEATHER: Professor Simon Shepherd led the construction of a massive new SuperDARN radar array in Oregon. Photograph courtesy of Simon Shepherd.

With 16 transmitters per radar sending up to a kilowatt of radio waves several thousand kilometers away, the radars are the latest addition to the international Super Dual Auroral Radar Network (SuperDARN), a series of radars covering polar latitudes and now expanding into middle latitudes to increase views of electromagnetic activity.

Learning more about plasma, the ionized matter that comprises more than 99 percent of space, goes beyond pure science. “We are interested in space weather because it can have negative effects on society,” says Shepherd. “Satellites spend their time in an environment that is extremely variable and not as well understood as we would like. Solar events can disrupt communication with satellites, shorten their lifetimes, or in extreme cases, cause them to fail. If radio or satellite communication with ships or planes is lost, the results could be disastrous.”

Geomagnetic storms can wreak other havoc as well, including knocking out electric power and causing corrosion in oil and gas pipelines. “If we could predict when and where these events occur, we would be able to take various protective measures such as rerouting planes and electric power, and putting satellites in ‘safe’ modes,” says Shepherd. “We want to be able to predict space weather, just like terrestrial weather forecasts.”

Shepherd’s Oregon radars are part of a National Science Foundation-funded collaboration with colleagues at Virginia Tech, the University of Alaska, Fairbanks, and Johns Hopkins University for constructing radars in four mid-latitude locations, with each colleague overseeing at least one of the projects. Shepherd prefabbed thousands of parts for the radars at Thayer, with help from Vipul Kakkad ’13, Matthew Knight ’11, and Ph.D. student Ellen Pettigrew Cousins ’08. The Thayer team spent several weeks in Oregon working with construction crews to turn those parts into working radars. The first transmission occurred November 25, 2010, Thanksgiving Day.

Shepherd, who continues the work in Oregon, will host a SuperDARN conference at Thayer School May 30–June 3. See the SuperDARN website to view plasma convection images and more radar construction photos.